Roaming is the ability to make and receive calls outside of a user's home network. International roaming, more specifically, is the ability make and receive calls from a foreign country, using the user's own handset and the foreign country's wireless network. Typically, international roaming requires a user to dial an international access code to reach a telephone number outside of the country where the user is located. International access codes are specific to each country and, in some cases, to the carrier whose network supports the call. For example, a user in the United States must dial “011” on his handset in order to use the international roaming feature to place an international call. A user in France would dial “00,” “40,” or “70,” or another international access code, depending on which carrier he chooses to utilize, in order to place an international call from France. Therefore, users who frequently travel must keep track of a variety of different international access codes in order to use their handsets to make phone calls in different countries. Because many countries have different international access codes, and because the international access codes within a single country may vary according to carrier, accurate knowledge of the codes may be a significant burden on travelers.
Many European countries utilize the Global System for Mobile Communications (GSM) standard for wireless networks. GSM supports an international dialing feature in which users may dial a (+) key on their handset in lieu of dialing the international access code. Dialing the (+) key marks the call as an international call, instructing the local switching system to route the call to an international switch. Unfortunately, users whose handsets include the GSM-supported (+) key cannot utilize this function in areas that are not covered by a GSM network. For example, code division multiple access (CDMA) systems do not recognize or support the mark accompanied by a call that has been placed with a (+) key, and are therefore unable to route it to an international switch. Instead, in order to route an international call, CDMA systems require the appropriate international access code to accompany the call.
With the tremendous increase in wireless communications over the past years, there has been a demand for simpler access procedures when roaming internationally. However, there currently does not exist an automated international dialing feature allowing users to engage in international roaming, regardless of the network supporting the call, without knowing and entering the proper international access code.